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Date: Tue, 20 Dec 2011 16:25:58 +0000
Subject: Re: nesting context managers
From: Rami Chowdhury <rami.chowdhury@gmail.com>
To: Ulrich Eckhardt <ulrich.eckhardt@dominolaser.com>
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On Tue, Dec 20, 2011 at 14:15, Ulrich Eckhardt
<ulrich.eckhardt@dominolaser.com> wrote:
> Hi!
>
> Let us assume I had a class HTTPClient that has a socket for HTTP and a
> logfile for filing logs. I want to make this HTTPClient a context manager=
,
> so that I can write
>
> =C2=A0with HTTPClient(url) as client:
> =C2=A0 =C2=A0 =C2=A0pass
>
> and reliably have both the socket and the logfile closed. The easy way is
> wrong
>
> =C2=A0def __enter__(self):
> =C2=A0 =C2=A0 =C2=A0with self._mysock, self._myfile:
> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0return self
>

It seems like some of the functions in the contextlib module might
help? You could try and reorganize your code so that you can use the
@contextmanager decorator, for instance?

That having been said, it doesn't seem that difficult to me to code
your own simple __exit__ method if you're already coding up __enter__
?

HTH,
Rami

--=20
Rami Chowdhury
"Never assume malice when stupidity will suffice." -- Hanlon's Razor
+44-7581-430-517 / +1-408-597-7068 / +88-0189-245544